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I have been working with one project which require 12 V power supply with at least 1.5 A current. I used TI Webench power designer tool to create simple 5-10 V input and 12 V 2 A output design. Since input voltage is controlled, we can provide from 5 to 12 V, but since 12 V to 12 V boost converter is not very practical, I searched for design that is in 5 - 10 V. I used this one: https://webench.ti.com/appinfo/webench/scripts/SDP.cgi?ID=DF5A3A9BDBFC47F7

Manufactured PCB design and assembled whole device with proper components. But the problem is that the output is very noisy. At most, our system consumes around 700 mA, so I tested this scenario with 17 ohm power resistor directly connected to this converter output. I measured input and output voltage with osciloscope, I also used lab bench power supply with 10 V 2.2 A output. Yellow signal is the input and Blue signal is the output of TPS61088 converter. Why it gets so noisy? Load doesn't consume 1 A. It even effects the input, how can I solve this problem? enter image description here My capacitors are 16 VDC, so I tried switching them to 35 VDC for DC bias effects, I also tried using 470 uF input electrolytic capacitor, I tried using thicker wires but nothing seems to help. What else can cause these big ripples? Here is the schematic enter image description here I probed signal directly on C8 capacitor using ground clip on capacitor GND pins and signal probe on capacitor Vin pin. Here are Capacitors and inductors that I used from mouser: C1- GCM1555C1H561GA16D

C2,C6- C0603C104J3RACTU

C3,C11- GRM21BR61C226ME44K

C4- GRM155R71C822KA01D

C5- CC0603JRNPO7BN270

C7- C0603C105K4PAC7411

C8- MSASE31LBB5476MTNA01

C12- 0402YG104ZAT4A

L1- EXLA1V0402-R68-R

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    \$\begingroup\$ Please show the schematic, and what components you used, particularly MFG/PN of the input and output capacitors, and inductor. \$\endgroup\$ Commented May 16 at 7:27
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    \$\begingroup\$ And show how you probe the output. \$\endgroup\$ Commented May 16 at 7:29
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    \$\begingroup\$ @Dominykas MFG/PN means "manufacturer part number". \$\endgroup\$ Commented May 16 at 8:14
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    \$\begingroup\$ I probed signal directly on C8 capacitor. this doesn't answer the question of how you probed the input and output. What I meant was if you probed with the ground clip attached (terrible way) or without the ground clip (proper way). \$\endgroup\$ Commented May 16 at 8:23
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    \$\begingroup\$ I probed signal directly on C8 capacitor using ground clip on capacitor GND pins and signal probe on capacitor Vin pin. okay. Thanks for the update. Now re-take the measurements using the proper way that I've shown in my previous comment and see if the unwanted spikes are still there. \$\endgroup\$ Commented May 16 at 9:14

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